Though 30 years have passed, remorse, sighs and sympathy were common feelings among attendees who convened a seminar in this capital city of central Henan Province to commemorate an accident that had long been ignored nationwide.

A miserable story about China's most devastating dams bursts that caused thousands of lives in the province in August 1975 was unfolded by 150 officials, meteorologists, hydrologists from China, the United States and Italy at the seminar on Sept. 15, only three days after China announced to declassify its natural disaster death tolls. HORRIBLE MEMORIES

On Aug. 7, 1975, just a day before the tragedy, all most nobody in Zhumadian, a city about 1,000 km south of Beijing in Henan, were aware that a catastrophe was looming.

A pouring rain following the third typhoon that battered China that year soaked the area with then about 7 million population, swollen more than 100 medium or small reservoirs with a rainfall recorded at 1,060 millimeter in 24 hours near the typhoon center.

"When the rain continued, the days were like nights as rain fell like arrows," survivors were quoted as saying by official records. "The mountains were covered all over by dead sparrows after the rain."

The 24.5-meter dam of Banqiao Reservoir which took over the most rain from the typhoon first breached at wee hours of Aug. 8, releasing within six hours 700 million cubic meters of floods that wiped Daowencheng Commune downstream immediately from the map, killing all 9,600 citizens.

"The blare of the dam burst sounded like the sky was collapsing and the earth was cracking," survivors recalled. "Houses and trees disappeared all in a instant. Numerous corpses and bodies of cattle floated in water amid people's wailing for help."

To worsen the situation, the dams of the city's other 61 reservoirs collapsed one after another within a short period, unleashing about 6 billion cubic meters of floods to an area of about 10,000 square kilometers.

Official statistics recorded 30 years after the dams bursts show more than 26,000 people were killed in the floods, the life of more than 10 million people was affected and all communication to and from the city were cut off. But some meteorologists and researchers said the figure might be even bigger.

"The number may be revised some day in future," said Wang Yanrong, an official with Henan Province Department of Water Resources who has studied the province's flood disaster death tolls for years. "It depends on further and more thorough study of related files, documents and our data." CHAIN-REACTING FAILURES

Though such appalling images of the dams burst, however, were not publicized during that time when Chinese leaders considered natural disaster death tolls a state secret, an investigation by central government soon after the floods found a series of "unexpected failures" led to the nightmare.

Xinhua learned that only a rainfall of 100 millimeters was forecast by the Beijing-based Central Meteorological Observatory forecast before the 1975 typhoon because no meteorologists in China then could reach an accurate prediction "given their scientific knowledge".

Water resources researchers said the design of those reservoirs and the guiding principles to contain the might Huaihe River should be blamed for such a calamity.

"The problem was not only the weather forecast," said Li Zechun, who first arrived at the scene as a weather forecaster after the floods 30 years ago and now an Academician of the Chinese Academy of Engineering Sciences, "that tragedy was a man-made calamity rather than a natural one."

Li said the water storage for irrigation function of a reservoir was overemphasized amid reservoir construction heat in the late 1959s despite warnings by some scientists that much of a reservoir's flood control was ignored.

The Banqiao Reservoir, which first collapsed, for example, was designed with only a capacity of 492 million cubic meters but it had to accommodate more than 697 million cubic meters of floods then.

The absence of an early-warning system or evacuation plan then also made the flooded areas quickly descended into chaos, Li said. LIVE WITH FUTURE FLOODS

Since floods and drought are a fact of life for much of China, academics said, Chinese should be prepared for any devastating floods in the future.

"Henan still has an arduous task in flood control in future," said Kong Haijiang, a researcher with Henan Province Meteorological Observatory.

Kong estimated that a landfall of typhoon might cause a regional torrential rain similar to that in 1975. "We need to be prepared."

Other new threats in future floods have already emerged, said Li Zechun, the academician, such as the fast development of chemical industry in reservoir areas.

"Once the chemical plants are flooded, the contamination to the environment is immeasurable," Li said, "we have already witnessed such results in New Orleans from Hurricane Katrina."

Li said to prepare for future floods, a data base consisting of meteorological, hydrological, environmental protection, forestry and agricultural departments should be established first to form a uniform environment monitoring networks.

At the same time, Li said, the best way to prevent and control natural disasters was to have an early-warning system with a safe communication system.

"Had the communication in the reservoir areas not been cut off in 1975, " he said, "more lives would have had been saved in downstream."